Forty-four percent of Americans have either switched their religious affiliation since childhood or dropped out of any formal religious group, according to the largest recent survey on American religious identification.

The 44 percent figure includes people who switch affiliations within one of the major faith traditions, such as a Protestant who goes from Baptist to Methodist. Counting only people who switch traditions altogether — say, from Catholic to Orthodox, or Protestant to Muslim — the number drops to 28 percent.

I gotta tell you going from Baptist to Methodist in the US Protestant religious culture (still 51% according to the survey–total Christian=78%) is almost not really a change. Affiliations switch within those denominations–and always have in the US non-state church system–because the family moves somewhere and the other church is closer. Or they like the preacher and the people better at the new church. Or the husband used to go to a Methodist church then married a Baptist woman so they go to her church now.

Now the last sentence itself still is problematic. Switching from Catholic to Orthodox is still within Christianity and while there are certainly differences, theologically and liturgically they are very similar to one another (different culturally). So questionable whether that counts as a separate tradition.

Protestant (i.e. Christian) to Muslim does. So I wonder if they cut out the Catholic-Orthodox (and similar pairings) how many actual tradition-shifts there are?

This actually is the most telling stat to me:

The survey also concluded that 16 percent of American adults are not affiliated with any faith today. About 4 percent describe themselves as atheist or agnostic. Young adults ages 18 to 29 are much more likely than people 70 and older to say they are unaffiliated with any particular religion, Pew found.

So 96% of even the unaffiliated religiously still believe in some Higher Power/God-figure. And typically young people are more likely to not be religiously affiliated–though that tends to (not automatically but tends to) if and when they get married and have children.